overall traffic may be up because some content pages ranking increased, or seasonality, or some other factor, point being, looking at overall traffic won't help you diagnose the situation. you need to segment the traffic by source and page and see if the traffic you expect to convert, is converting at the rate you expect it to. segmenting traffic, sales, sources are all important to assembling the puzzle, to make meaning of it, so it can be improved and optimized.
one nice thing about ppc is the speed and flexibility of traffic, and therefore, data collection. think of paid search and organic as partners who help each other. segment the data so you understand each separately. once you reach that level, organic traffic can help you uncover new areas to ppc. and ppc successes can lead to targets for your organic efforts.